* {
  margin: 0;
  padding: 0; }

body {
  background-color: #f9f9f9;
  font: 18px Helvetica, Arial, sans-serif;
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0; }

.wrapper {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-align: center;
      -ms-flex-align: center;
          align-items: center;
  -webkit-box-pack: center;
      -ms-flex-pack: center;
          justify-content: center;
  -webkit-box-orient: vertical;
  -webkit-box-direction: normal;
      -ms-flex-direction: column;
          flex-direction: column; }

input {
  font: 24px Helvetica, Arial, sans-serif;
  padding: 0.3em;
  text-align: center;
  border: 1px solid #ccc; }

#form {
  text-align: center;
  z-index: 1000; }

#ratio {
  z-index: 500;
  opacity: 0;
  background-color: #eee;
  height: 0%;
  width: 0%;
  border: 1px dotted #ccc;
  -webkit-transition: width 0.5s ease-in-out, height 0.5s ease-in-out, opacity 0.5s ease-in-out;
  transition: width 0.5s ease-in-out, height 0.5s ease-in-out, opacity 0.5s ease-in-out; }

h1, p {
  margin-bottom: 1em;
  text-align: center; }

@media screen and (max-width: 500px) {
  p input, p span {
    display: block;
    margin: 5px auto;
    text-align: center; } }